The present invention relates to an apparatus for dispensing pieces of paper or like web material from the bottom of a dispenser while minimizing the pressure and accompanying friction experienced by the piece of web material.
In conventional dispensers for Z-folded or fan-folded paper towelling, the towel web is drawn from the bottom of the dispenser. As the web is withdrawn, the weight of the stack against the bottom support rollers in the dispenser creates friction which makes it difficult to withdraw relatively weak-strength paper towelling without breaking or tearing, especially if the user has wet hands contacting and further weakening the paper towelling. With short stacks of towelling in the dispenser, such friction is generally low and usually is not sufficient to cause breakage or tearing. However, when multiple packages of towelling are loaded into the dispenser, the friction is sufficiently high, and it does lead to breaking or tearing of the towel when it is withdrawn from the dispenser.
Various devices for dispensing fan-folded sheet material have been proposed. West in U.S. Pat. No. 2,195,437 teaches an invention in which a portion of the interior walls is roughened or corrugated to impart friction to the stack of tissues. The increased friction lessens the tendency for multiple tissues to be pulled from the dispenser at the same time.
Carlson in U.S. Pat. No. 1,681,840 teaches an invention in which the stack of web material is supported at one edge by a narrow supporting shelf and at the other edge by a spring-loaded finger. Supporting the towel stack along its edges permits the lower side of the stack to be bowed downwardly such that slight tension is exerted on the lower towels to facilitate the removal of the towels from the dispenser.
Hoberg in U.S. Pat. No. 1,605,231 teaches an invention in which reversely curved supporting members including crowned portions are provided. The crowned portions tend to comprise the principal support for the interfolded sheets, thereby decreasing the pressure and accompanying friction on the interfolded sheets adjacent the folded margins. Flanges are also provided to support the edges of the towel stack. The flanges take part of the weight of the stack at its interfolded edges off the bottom of the dispenser. Removing the weight from the interfolded ends allows the end of the next sheet to be removed from the dispenser with greater ease.
Casterline et al. in U.S. Pat. No. 744,047 teach an invention in which a pair of retarding devices are provided to bear against the sides of the stack of material. The retarding devices provide a lateral force against the stack and support much of the weight of the stack above the retarding devices, thereby decreasing the pressure on the bottommost piece of web material. The retarding devices permit uniform pressure at the discharge opening regardless of the weight or size of the stack.
In dispensers for fan-folded web material, it is important to minimize the pressure and friction experienced by the bottommost piece of web material. In the ideal dispenser such pressure and friction can be minimized by the application of a lateral force. The lateral force and accompanying lateral pressure should be sensitive to the amount of web material present in the dispenser, i.e., the mechanism providing the lateral force should be self-adjusting to increase the lateral pressure when an increased amount of web material is provided. The prior art does not disclose such a dispenser.